/*
 * Copyright (c) 2020 Pantheon Technologies s.r.o. and others.  All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
 * and is available at http://www.eclipse.org/legal/epl-v10.html
 */

package org.opendaylight.netconf.mdsal.notification.impl;

import java.util.Collection;
import org.eclipse.jdt.annotation.NonNull;
import org.opendaylight.mdsal.binding.api.DataBroker;
import org.opendaylight.mdsal.binding.api.DataObjectModification;
import org.opendaylight.mdsal.binding.api.DataTreeModification;
import org.opendaylight.netconf.notifications.NetconfNotificationCollector;
import org.opendaylight.netconf.notifications.YangLibraryPublisherRegistration;
import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.yang.library.rev190104.YangLibrary;
import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.yang.library.rev190104.YangLibraryUpdate;
import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.yang.library.rev190104.YangLibraryUpdateBuilder;
import org.opendaylight.yangtools.concepts.ListenerRegistration;
import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;

/**
 * Listens on the modules, submodules, datastores, and datastore schemas changes in data store and publishes
 * to base netconf notification stream listener a server-specific identifier representing
 * the current set of modules, submodules, datastores, and datastore schemas.
 */
public final class YangLibraryNotificationProducerRFC8525 extends OperationalDatastoreListener<YangLibrary>
        implements AutoCloseable {

    private static final InstanceIdentifier<YangLibrary> YANG_LIBRARY_INSTANCE_IDENTIFIER =
            InstanceIdentifier.create(YangLibrary.class);

    private final ListenerRegistration<?> yangLibraryChangeListenerRegistration;
    private final YangLibraryPublisherRegistration yangLibraryPublisherRegistration;

    public YangLibraryNotificationProducerRFC8525(final NetconfNotificationCollector netconfNotificationCollector,
                                           final DataBroker dataBroker) {
        super(YANG_LIBRARY_INSTANCE_IDENTIFIER);
        this.yangLibraryPublisherRegistration = netconfNotificationCollector.registerYangLibraryPublisher();
        this.yangLibraryChangeListenerRegistration = registerOnChanges(dataBroker);
    }

    @Override
    public void onDataTreeChanged(@NonNull Collection<DataTreeModification<YangLibrary>> changes) {
        for (DataTreeModification<YangLibrary> change : changes) {
            final DataObjectModification<YangLibrary> rootNode = change.getRootNode();
            final YangLibrary dataAfter = rootNode.getDataAfter();
            if (dataAfter != null) {
                final YangLibraryUpdate yangLibraryUpdate = new YangLibraryUpdateBuilder()
                        .setContentId(dataAfter.getContentId())
                        .build();
                yangLibraryPublisherRegistration.onYangLibraryUpdate(yangLibraryUpdate);
            }
        }
    }

    /**
     * Invoked by blueprint.
     */
    @Override
    public void close() {
        if (yangLibraryPublisherRegistration != null) {
            yangLibraryPublisherRegistration.close();
        }
        if (yangLibraryChangeListenerRegistration != null) {
            yangLibraryChangeListenerRegistration.close();
        }
    }
}